So, visually you can try something called personal bubble. You can draw pictures and or use real pictures drawing the bubbles. He has his bubble, you have your bubble, other people have their bubble. You can't get closer than someone's bubble. For touching, hands in pocket please or hands in lap. You can try a game the whole class does of robot arms. Reach arms out in front and to the side. These are robot arms. No one can get closer than robot arms. Then quiet robot arm or space bubble reminders (without an upset tone, just a reminder). This worked for my son. We also did a lot of choice giving "do you want to sit in the circle in your space bubble, in a chair along the side (comfy chair like bean bag), or at your table? They choose. Not just redirected but given power of acceptable choices.